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An anonymous reader writes "Check out the latest success of the OpenSCAD 3d-printed electronics library. To use it, you just need a 3D printer and some conductive thread. OpenSCAD generates a component holder, and conductive thread wraps it all together — no solder, no etching chemicals, no sending out for anything. The instructable takes you through all the steps from schematic to circuit, and includes a more useful example: the fully printed LED flashlight."

It's a neat idea, kind of fun for first circuits. Some people in the RepRap community have been experimenting with directly printing circuits [reprap.org]. It would be very neat to see that come to fruition.

Badly, almost certainly.
Think of it as a poor man's wire-wrap system and make comparisons to that.

The conductive thread has a lot more resistance than real wire-wrap wire
(I would have used wire-wrap wire with stripped ends instead of conductive thread for this reason alone).
You don't get the gas-tight connections that you get where wire-wrap wire is pulled over the corner of a square post,
so there's potential for long-term oxidation and increased resistance
(to the point of appearing to be an open circuit at low voltages).
Since the "wires" aren't insulated,
stretching or sagging from any loss of tension runs the risk of shorting two connections.
It's going to be even more prone to loosening from vibration and flexing than wire-wrap.

This is a very important point of course, because the intention is actually to build something that is production grade (obviously a ways off). But so far I have been actually pretty impressed. The durability of the plastic is extremely impressive (ABS == lego plastic, and my legos have lasted forever..) -- obviously you're mostly wondering about the durability of the circuits. Now I've only built a handful of flashlights which have only been around a few weeks (distributed to a few friends as

You could probably do multi-plane boards with less trouble, not having to have the through holes go all the way through the board, just to connect the two planes. You could probably make multiple planes that are just resistors, or even capacitors, printed onto the substrate. They already do a lot of this stuff, I've seen boards with zig-zaggy areas that certainly appear to be resistors (not the zig zags that keep the interconnects the same length, but at right angles to each other and wrapping back onto themselves). Possibly even small transformers?

On the other hand, "conductive thread" doesn't really sound like it is going to conduct much current, so you'd probably have to have a machine that can actually print metal.

Yea, just make a multi-plane board, and have smaller and less heat sensitive components in the middle layers, and the larger and heat sensitive ones on the outer boards.

You could still use solder, just have the PCB built up around the component and solder; or have it done as a post for the through "hole" and have the surface component solder onto that same post and connect to the resistor underneath.

Any time you mention "solder", remember the temps involved and that the plastic structure used in the construction has to withstand those temperatures. Standard FR4 printed circuit board material (fiberglass reinforced, non-reversible heatset resin) is remarkably tough stuff. Even the most heat-resistant thermoplastics the industrial 3D printing suppliers are making available are questionable for standard soldering temperatures. And it's not clear that the hobbyist printers can produce the temperatures necessary to work with those higher-melting-point thermoplastics.

Um, embedded printed resistors and capacitors have been around for decades. This "3d printing" fad is just preying on the ignorance and touching naiveté of the computer generation. You think everything just popped into existence five minutes ago and that people before were complete, drooling retards. Newsflash: PCBs have been around for decades and they are now approahcing the same density and complexity as early ICs. You think you'll be getting anywhere near that in your living room? Um, no?

+1 Informative. I agree. It'd be way more useful if they had shown how to use a printer (not necessarily a 3D one!) to print resistors on a PCB. Having a cheap way to print bulk resistive material on top of a PCB, and then using a laser "router" to trim those, would be a nice way to get higher density prototype boards without dealing with 0402 parts (those parts are 20mils wide -- about as wide as signal traces were on cheap PCBs in the 80s).

Newsflash: PCBs have been around for decades and they are now approahcing the same density and complexity as early ICs. You think you'll be getting anywhere near that in your living room? Um, no?

No, but the equipment to produce them costs somewhat more than the $2,000 a 3d printer will set you back, and will take up a lot more space than most people have available. Alternatively, hiring other people who already have the equipment will set you back $50 or so per board for small quantity orders.

The fact that this could possibly be done with reasonably cheap equipment that a hobbyist can feasibly afford *is* a breakthrough. Yes, it's irrelevant to the professionals who will continue to do things in the better way that requires more expensive equipment, but for the rest of us, this kind of thing is important.

I'm calling observer bias on this. I can't remember the last time I've seen someone use stripboard for a hobby project. Veroboard seems to be far more common by a long shot on most projects floating around the internet.

That said if Hackaday is anything to go by, etching your own circuit boards using a variety of refined techniques is the real choice for hobbyists these days. It's cheap, very easy to do, and these days is only really not a choice if you want tiny through plated vias or >2 layers of traces

Yes, but not for long. More and more projects, at least in my experience, are requiring components that aren't available with 2.54mm pin spacing, leaving stripboard a rather antiquated system that will soon be almost useless except for beginners' projects.

1.) photo lithography. Print your traces to a transparency. Attach to a treated PCB. expose to UV for a few minutes. Develop; etch. Costs about a hundred bucks for the equipment, and a few bucks per board.

2.) Laser print- there are a couple of variations, some use special transfer paper (press-n-peel, pcbfx), some print over color magazine photos. Heat & press image to PCB. Drop PCB+printed image (now fused together) into water to separate the PCB and toner fr

No, but the equipment to produce them costs somewhat more than the $2,000 a 3d printer will set you back, and will take up a lot more space than most people have available.

One type of prototyping PCB machine uses a 3-axis mill to cut traces into plain copper-clad boards. Got that - a 3 axis mill. All the rep-raps and such are already 3-axis machines. They just need a mill option to cut circuit boards. Not everything needs to be "additive" manufacturing. Also, once you have a mill you can cut sheet metal.

Could they in effect print or incorporate certain components inside the PCB board?

SMD resistors are pretty small, and if they were embedded it would free up more surface area for larger components and reduce overall size.

Not with this level of technology, no - what they have here is a way to print an insulating framework, into which you put parts and then wrap conducting wire. You'd have to wrap wire around the tiny SMD resistor for that to work.

I mean like 3D print a PCB, install and solder the parts and tracts. Print more of the PCB and install more parts, etc... Till you get to the surface level then install the larger components like normal. So instead of things being spread horizontally, you'll have many of the smaller parts now done vertically.

You do realize that the PCB can no longer be repaired if some of the buried parts were to fail or bad connections from this unproven process. Last thing you want in a prototype is some unproven process. Did the design failed or the manufacturing fail? Good luck on debugging that.

There is also the issue of disposal as now they can not be separated. Think that's not a problem for you? Think again... In EU, the manufacturer is responsible for properly disposing of the electronics they sell you. It would

At this point, I'm not certain that printed conductive paths are going to work for all applications. But this technology is already in use for printing etching/soldering masks on traditional board materials. Given some R&D into materials, a process involving building up a multi-layered board that includes plating steps to build up conductive paths alternated with board build-up could work.

For many applications, its not only the conductor characteristics that are important. The substrate (board) materi

So instead of using that icky earth destroying copper wire, it uses conductive thread. Thread is used by girls making craft projects, what an excellent correlation with the marketing campaign that only women like health and green (seriously, WTF is up with that?). Tada, conductive thread, its great!

Seriously, conductive thread is basically wire wrapping wire with yarn/thread except the connections aren't gas tight so its not as reliable. Wirewrap is great stuff, I built a 8051 based microcontroller in '91 and it still works. Its a 8052AH-BASIC which is basically a preprogrammed 8051, predating the identical concept BASIC-STAMP and more modern ARDUINO by a decade or two. Wire wrap is the opposite of automotive/industrial/aerospace grade as it is completely intolerant of vibration and moisture. Aside from that, its great. I would guess conductive thread would be the same.

Reading the articles, its a cool psuedo Manhattan style construction using little pegs and making the electrical contacts using the psuedo wirewrap thread. I like manhattan construction for experimental stuff... need another connection point? snap off a tiny piece of DS PCB and solder it to the groundplane...

Simplest similar design would be a 3-d printer that can print Kapton filament and regular ole solder paste and a hot air gun. One problem being that a lot of repraps use Kapton for their high temp parts, so you'd need something more exotic. Aside from my having no idea if Kapton is thermo-setting or thermo-plastic and being too lazy to look it up because it ain't happening anytime soon.

If you don't want to use conductive thread, silver bearing epoxy would probably work.

How about printing conductive epoxy and then press on the chips before the epoxy sets? You'd be stuck with planar layouts, but that would be fine for many circuits You could even do two-sided assemblies if you're willing to add drill stages and a second printing step.

If the burning point of the epoxy is higher than the melting point of the substrate, you can just print over it and melt on another layer, I suppose.Epoxy is a thermoset, it doesn't melt, just burns above 200 degrees C or so (depends on type).

The advantage is you can print and assemble the parts in just two process steps per side and eliminate the tooling costs. The trouble is I don't know if there's a suitable material available -- a printable conductive glue essentially.

The barrier to this approach for prototyping is you need a direct-printable conductive glue. I'd use this for proof-of-concept. For saleable items, I'd want something more robust.

Not impressed. I can hand solder a circuit smaller and much cheaper on standard proto board with plated through holes. Done this many times with better results. For circuits I am going to make more than 1 or 2 of just download the free ExpressPCB program and for around $55 you can three boards.

Heck, if you use thin laminate, and tweak your laser printer's fuser to run hotter, you can print directly on the laminate without any transfer steps. Print, etch, drill -- for one-sided boards it doesn't get much easier than that.

Heck, if you chemically treat the copper to give a less-reflective surface, and tweak your laser printer so the laser's hot enough (I recommend a Nd:YAG mod), you can just burn the circuit right there and skip etching, too.

How do you dispose of the used etchant? Do you have a fume hood for using it, or do you do it outside? Would you trust a child to use your etching method?

This technique isn't supposed to replace DIY PCB etching or soldering. It's another way of doing things that for some people will probably be a lot less of a headache and more fun. It's somewhere in-between DIY PCBs and one of those old "1000-in-1" electronics kits with the spring connectors.

Not impressed, my vacuum tubes were plenty good enough for adding and subtracting. They're cheaper than those new "transistors" too. I can put an array of tubes together for much cheaper than you can put transistors on a board.

I don't actually, I wasn't even trying to be funny. I was showing the absurdity of an argument like that, saying that something is unimpressive merely because you can do it cheaper and smaller a different way doesn't make that way necessarily better. This is the first use of this, much like anything else it can get smaller and faster as time goes on. How much fun would it be to have a small 3D printer on your desk to rapid prototype boards? Things like this eventually lead there.

Yeah, you can solder a much smaller project - and it would probably take twice as long to solder the circuit than it takes to wrap it.

This stuff is for prototyping and playing around with, not making production models. You could give something like this to a kid who doesn't know how to solder as an introduction to the idea of making circuits, for instance.

This stuff is for prototyping and playing around with, not making production models.

So, you already have breadboards, spring-based terminals (used in old teaching kits), and solder-based development pcb's. And my favourite - a sheet of thick non-conductive material (such as acetate-based or bakelite boards, or even cardboard) with holes punched in so you could assemble the connections on one side of the card. There were even tools for that - check http://en.wikipedia.org/wiki/Wiring_pencil [wikipedia.org]

But it will probably never work for real products. I'd never have the gall to sell an electronic product with connections made of conductive thread. I'd sooner hand-wire it together on perf board.

3D printing works if you need to make one or five objects that don't need to be very robust. But you don't have to get into very high numbers at all before it's cheaper get injection-molded custom parts that are much stronger.

Automated wire wrapping done with boxed wire was indeed used for spacecraft, satellites and aircraft in the 1960s and 1970s, but the technique largely fell out of favour due to cost (not reliability) reasons. Surface mount is the usual way now.

A good wire-wrap job can be very functional but it's not as reliable as soldered wires. You're relying in tension and pressure to make the metal-to-metal contact and the contacts are exposed to air and possibly water penetration. The solder connection is both lower resistance and has the electrical contact coated in solder. Solders are pretty resistant to corrosion and form a good seal against water and whatever corrosive materials it carries.

Wire wrap vs. conductive thread - wire wrap is air sealed so it doesn't corrode, giving it a decent working life and resistance to corrosion. Conductive thread is not air sealed, so it oxidises fairly quickly and fails.

Wire wrap vs. conductive thread - wire wrap is air sealed so it doesn't corrode, giving it a decent working life and resistance to corrosion. Conductive thread is not air sealed, so it oxidises fairly quickly and fails.

Wire wrap isn't air sealed at the joints. Conductive thread wicks water. Very bad for corrosion.

Actually even small quality injection molds can easily run into the multiple thousands of dollars, so while you're correct for commercial runs, for pretty much anything below that, i.e. most non-commercial parts, 3D printing is starting to look good, especially on the more robust commercial processes.

I'll grant you the strength issue - I think it'll be a while before 3D printers become competitive in that realm, though milling machines don't have that issue. The architectural school of "mass customization" is beginning to take advantage of this - it's no longer dramatically more expensive to cut custom parts from base stock than it is to cut standardized parts - it's all computer controlled and comes down to how long the cuts are and how much material is wasted do to poor component packing on the stock. Especially if a structure can be built from multiples of only a few custom pieces it can rapidly be built by a few people given a big pile of parts and lego-style assembly instructions, offsetting the higher component cost with lower assembly costs (fewer, and potentially less-skilled, man hours required)

At this point 3D printing is largely a hobbyist and prototyping tool, as is to be expected. After all it's only just starting to become affordable, and people are still exploring its potential. A few decades ago computers were in a similar sort of niche, relegated to hobbyists and research institutions. The 3D printing techniques that are being developed now are sort of the equivalent to the development of the bubble sort - poor performance, but it gets the job done, and thus expands the sphere of what's possible, allowing more hobbyists to explore a wider range of possible applications.

ugh yea ok BUT in less than half the time that 3D printers have been out personal computers went from nerds in garages to a mega industry where people were buying them up as fast as they can make them.

3D printers are NOT the next computer revolution, its already proven that, its more akin to the Laser Disc, its around, a very small subset of people will use it, and maybe in 30 years it may become the DVD if they can bring the cost and size down, and make the quality not suck.

I think you're jumping the gun a bit with that claim - the first non-human computer, Charles Babbage's difference engine, was designed in 1822s. The first programmable computer, Konrad Zuse's Z1, wasn't completed until 1938, and the first stored-program (i.e. software-driven) computer wasn't delivered until 1950. Even from there it took another 18 years until 1968 before the first mass-market computer, the HP 9100A, was sold, and we were in the mid-70s before computers were marketed to individuals rather

You are obviously too young to remember vacuum tubes.
I have been working in electronics since the early 70's as a kid, tv shops in the mid-late 70's.
I have watched circuits shrink over the years, from no circuit board (point wired tv chassis), to
huge printed circuit board, to the switch over from tubes to transistors (and the RCA nuvistor),
then onto LSI chips. A 25" color TV use to take two strong men to lift & move around. Now,
a housewife can hang one on a wall.
Given time, the 3d printing will shrink also.

If you can change 'ink' in the process of 'printing', just change it to a carbon based 'ink', then you can print more traditional traces. Then if you print more of your inert substrate over it, its even 'sealed' from the elements.

( and i know its not ink, i'm just sticking with the analogy of a printer )

So now we're using 3D printers to make things that are already printed in real life?

Next week, a 3D-printed book. No ink, kids! Just delicious ABS plastic pages with the letters raised from the surface.

All told, this works quite well as a parable for why the benefits of 3D printing will not lead to everyone manufacturing all their own consumer products at home, nor will manufacturers be replacing any substantial volume of their processes with 3D printing.

Actually not an entirely useless idea. Raised lettering sounds a lot like an old-fashioned printing plate. A 3d printer of sufficient resolution (one of the pricier models) could produce printing plates by that method, even if they aren't good for as long as a metal plate. While it'd still cost more per-page by far than a common laser printer, it'd be ideal for things like decorative wall markings or custom one-off ink stamps. So when you're doing, say, a special event requiring payment, you can print a sta

Depending on the use case you pick, there are processes which are inherently faster and higher quality, even for raised lettering, that already exist - just like for PCBs and books.

Additive manufacturing is generally only efficient at producing shapes on a one-off basis if they vary along more than two axes, on a bulk basis if they are impossible to manufacture by other means, or in the narrow margin in between where the batch is too small to take advantage of other scalable processes. It turns out that in

Additive manufacturing is generally only efficient at producing shapes on a one-off basis if they vary along more than two axes, on a bulk basis if they are impossible to manufacture by other means, or in the narrow margin in between where the batch is too small to take advantage of other scalable processes. It turns out that in real life there are very few things we use that match those criteria, and not many things that do that we would use if only it were easier to make them.

I should have been more specific, but the term "additive manufacturing" is usually used for processes that make 3D shapes out of homogeneous materials - especially in this context. Assembly, bonding, finishing, and other processes that combine materials are a different matter.

In the case of TFA, the assembly is all done by hand and the point of interest is the means of manufacture of the board that forms the structural base for the circuit. Never in a million years would you make a two-layer PCB that didn't

Okay, I'm sorry to say that from a glance at the TFA it looks like they're talking about installing the thread by hand, but if that part is automated it could open up new doors outside of electronics as well.

For example - when building up a structural component what if you lay down a "net" of polyester thread between layers - you could potentially get a dramatic increase in the strength and durability of the finished part, especially if you carefully aligned the thread to maximize it's impact.

I'm sorry, but the whole idea looks pretty dumb to me except for hobbyists to play around with (but without getting anything really useful as a result). Maybe if some key problems are solved it'll spawn a revolution in the electronics industry, but I don't see how (and if I did, I'd be revolutionizing the industry myself). The main problem I see here is the "conductive thread". It's not very conductive, nor is it durable or robust. It doesn't make good long-term connections with parts made primarily of

I'm surprised at how much hate and vitriol are being spewed here on slashdot. To the point of throwing around "geek" as an insult regarding this stuff. 3D printing is in its infancy, it's useful for rapid prototyping of things. Sure it has its drawbacks and limitations, but some of us are hackers (in the original sense of the term, not the MSM version) and tinkerers.

Sure, a lot of things on www.thingiverse.com (a repository for DIYers and digital objects) are just _more_ parts for _more_ 3D printers, but

The problem is that the geek world (no insult intended) is divided roughly into two camps: those who like that technology can help us do cool new things, and those who like to do things with cool new technology.

3D printing is a cool new technology but the spectrum of things for which it is or will be useful for is extremely limited. Electrical circuits are one example of something that will never, ever be made using 3D printing for reasons of usefulness. You can put almost all the "hate" down to the people

Electrical circuits are one example of something that will never, ever be made using 3D printing for reasons of usefulness.

You don't know that. You're absolutely right that this particular technology is useless for anything actually useful, however never say "never"; you don't know if someone will come up with something that really is better than the current state-of-the-art. I agree it's pretty dubious; the fundamental problem is that for electronics work, you need a good way of making electrical interco

With some commercial STL machines (not the amateur ones) you can lay down multiple materials with different properties. Mark Cutkosky [stanford.edu] at Stanford has done this for some flexible robot parts. He's trying for biological-like structures, where everything is flexible but still highly structured.

... they are flattered that we are trying to imitate their technology.

Back before we really understood pcb technology and clock speeds were low, automated wire wrap was a viable technology. For a few years that was THE way to make a computer backplane. The technology had some surprising advantages. One, that wasn't obvious, was that the equipment was robust in a heavy vibration environment.

We could do conductive thread (or thin wire) but not using wire wrap. Mark Tilden showed that connections can be don

Should have purged the machine and made a final pass with conductive resin loaded in the machine. Then the machine could have printed the circuit traces on the surface of the part.
For what it's worth, this is reminiscent of old Radio Shack kits.